Quantum metrology studies the use of quantum states, interference, and entanglement in precision measurement. Originally developed for interferometric measurement of gravitational waves, in recent years quantum metrology has expanded both theoretically and experimentally to become a general technique with application in several areas. I will describe experimental work using ensembles of cold rubidium, an interesting quantum system for measurement of magnetic fields. Using optical probes and paramagnetic Faraday rotation, we demonstrate quantum non-demolition measurement of spins at the projection-noise limit. If time permits, I will discuss the use of nonlinear Faraday rotation to make measurements with scaling better than the "Heisenberg limit" of
SPECIAL JOINT QOAMO AND CQIQC SEMINAR
Please note non- standard day and time.